For many elderly individuals and other individuals with physical disadvantages, the propensity to fall and the risk of injury therefrom increases over time. According to U.S. health statistics, one out of three adults age 65 and older falls each year, and these fall events are a leading cause of injury and death for this age segment. Falls are the most common cause of injuries and hospital admissions for trauma such as lacerations, hip fractures and head trauma. Serious injury due to a fall may prevent a person from immediately contacting medical personnel or a caregiver, thereby exacerbating the injuries suffered.
In response to this problem, personal emergency reporting systems have evolved. Conventional personal emergency reporting systems sometimes take the form of an apparatus that a user keeps on their person and that includes a help button or switch that is pressed to alert others of a fall that requires help. The device may be worn on the wrist, attached to a belt, or carried in a pocket or purse, for example. However, depending on the severity of the injury, the user may not be able to reach and/or push the help button. For this reason, personal emergency reporting systems with embedded fall detection technology in their transmitters have evolved. An example of such a system is shown in FIG. 6. Detection apparatus 600 is worn by a user and has a fall detection sensor that incorporates an accelerometer and/or altimeter to record input data that is then processed using local firmware stored on apparatus 600 to determine the probability of a fall event. Upon determining based on the sensor data that a fall event has likely occurred, apparatus 600 automatically initiates and transmits an alarm event to a predetermined central monitoring station or server 610 and call center 620, typically via a personal emergency reporting system home console.
False positive fall detections are a significant problem with such systems. To help avoid false detections, the best location for the detection apparatus is on the user's torso, such as by being attached to a belt. However, users overwhelming prefer a detection apparatus that is configured as a necklace. In conventional necklace-type detection systems, the fall detection apparatus along with a battery is embedded within a pendant that is fastened to lanyard (necklace) and worn around the neck. As many fall detection devices incorporate an accelerometer, a challenge with having a fall detection device that is worn as a pendant around the neck is the high probability of a false positive fall detection due to excessive movement or swaying of the pendant during normal activities such as walking, moving from a standing position to a sitting position, or from a seated position to lying down. The pendant may also inadvertently hit an object such as a table or chair as the user changes positions from sitting to standing or from standing to sitting. Such an impact may generate a false positive fall detection in a device configured to detect shock as a fall event.
Thus, known necklace designs that use an accelerometer-based sensor in the pendant to measure acceleration, orientation and/or deviations from movement patterns increase the risk of generating false positive events due to the high propensity of excessive, non-regular and non-predictable movement or swaying of the pendant as a result of normal daily activities.
While accurately detecting and reporting fall events has substantial and tangible benefits, the ability to predict the likelihood of a fall event occurring based on movement patterns is arguably even more valuable. Fall prediction may be accomplished by identifying deviations in a person's gait from an established standard or “normal” gait of that particular individual. As with fall detection, a necklace design with an accelerometer embedded in the pendant makes fall prediction particularly difficult due to the propensity for excessive movement and swinging of the pendant. For this reason, in order to accurately measure and monitor an individual's gait for purposes of fall prediction, known devices must either be attached to or worn closely to the body.
The ability to remotely monitor movement and activity levels is also important in the elderly care industry from both wellness and security perspectives. However, for the same reasons as discussed above, a swinging pendant with an embedded accelerometer will less accurately measure the true activity level of an individual than will a device that is attached to or worn closely to the body.
Despite these disadvantages associated with known movement detection devices incorporating an accelerometer in a pendant of a necklace, as mentioned above, users overwhelmingly prefer this configuration to other configurations, such as a device attached to a belt. For this reason, there is a need for a necklace motion sensing system that provides a high degree of accuracy in motion sensing and detection of fall events, despite movement and swinging of the pendant.